Caption: Apollo 17 Apollo Lunar Surface Experiments Package (ALSEP) on the lunar surface. This consists of equipment carried by astronauts to the moon, set up there and left behind to transmit information back to earth. ALSEP was used on the Apollo 11-17 missions. Seen here are the Lunar Ejecta and Meteorites (LEAM) experiment (foreground), the central station (gold, upper centre), and the Radioisotope Thermoelectric Generator (RTG, upper right). Apollo 17 was launched on 7 December 1972. Photographed on 11 December 1972.